Magnetic resonance elastography for examining developmental changes in the mechanical properties of the brain

Abstract

Magnetic resonance elastography (MRE) is a quantitative imaging technique for noninvasively characterizing tissue mechanical properties, and has recently emerged as a valuable tool for neuroimaging. The measured mechanical properties reflect the microstructural composition and organization of neural tissue, and have shown significant effects in many neurological conditions and normal, healthy aging, and evidence has emerged supporting novel relationships between mechanical structure and cognitive function. The sensitivity of MRE to brain structure, function, and health make it an ideal technique for studying the developing brain; however, brain MRE studies on children and adolescents have only just begun. In this article, we review brain MRE and its findings, discuss its potential role in developmental neuroimaging, and provide suggestions for researchers interested in adopting this technique.

Keywords: Brain; Development; Elastography; Stiffness; Viscoelasticity.

Fig. 1

Overview of MRE data acquisition and processing: (A) An external mechanical actuator is used to lightly vibrate the head and generate shear deformations in brain tissue; (B) specialized phase-contrast MRI sequences image the resulting deformation through synchronization with applied vibration; and (C) an inversion algorithm is used to calculate the mechanical property distribution from imaged wave field.